Fixed a bug that prevented writing to the wave RAM, as well as a bug where the wave RAM was treated as zeros despite not being zero’d out

This commit is contained in:
Lior Halphon 2019-06-29 14:03:42 +03:00
parent 23229f1118
commit 4541efe86a

View File

@ -506,6 +506,11 @@ void GB_apu_run(GB_gameboy_t *gb)
void GB_apu_init(GB_gameboy_t *gb)
{
memset(&gb->apu, 0, sizeof(gb->apu));
/* Restore the wave form */
for (unsigned reg = GB_IO_WAV_START; reg <= GB_IO_WAV_END; reg++) {
gb->apu.wave_channel.wave_form[(reg - GB_IO_WAV_START) * 2] = gb->io_registers[reg] >> 4;
gb->apu.wave_channel.wave_form[(reg - GB_IO_WAV_START) * 2 + 1] = gb->io_registers[reg] & 0xF;
}
gb->apu.lf_div = 1;
/* APU glitch: When turning the APU on while DIV's bit 4 (or 5 in double speed mode) is on,
the first DIV/APU event is skipped. */
@ -556,7 +561,7 @@ uint8_t GB_apu_read(GB_gameboy_t *gb, uint8_t reg)
void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
{
if (!gb->apu.global_enable && reg != GB_IO_NR52 && (GB_is_cgb(gb) ||
if (!gb->apu.global_enable && reg != GB_IO_NR52 && reg < GB_IO_WAV_START && (GB_is_cgb(gb) ||
(
reg != GB_IO_NR11 &&
reg != GB_IO_NR21 &&